EVALUATION OF THE ANTIOXIDANT CAPACITY OF PHENOLIC EXTRACTS OF TWO LOCAL PLANTS: PLANTAGO CILIATA (DESF) AND THYMELAEA MICROPHYLLA (COSS. ET DUR)

The antioxidant capacity of aerial parts extracts of Plantago ciliata and Thymelaea microphylla has been studied. The quantitative estimation of total phenolics and flavonoids revealed that Thymelaea microphylla had the highest total phenolic content  (12.33 ± 0.01-4.35 ± 0.04 mg GAE / g) and flavonoids (5.2 ± 0.08-1.09 ± 0.05 mg CaE / g) when compared to Plantago ciliata extracts. However, the highest total phenols and flavonoids contents were obtained using methanol/water (80/20) as extraction solvent system. The antiradical power measured by the DPPH assay showed that PM3 extract exhibited significantly higher antioxidant effect when compared with standard antioxidants (BHA, Vit. C and Vit. E) with an EC 50 value equal to 3.50 ± 0.05 mg / l. On the other hand, all tested extracts revealed reducing powers measured by the PPM method higher than standard antioxidants.